Process and multiple pump apparatus for controlling the preparation of beverages

ABSTRACT

A dispensing apparatus for hot beverages is provided with means ( 4,5 ) to filter hot pressurised water through ground edible ingredients such as coffee, tea or herbal remedies in a chamber, has two or more pumps to feed water to said brewing chamber ( 2,82 ); the pumps are connected in series.

FIELD OF THE INVENTION

The present invention relates to a process and a multiple pump apparatusfor controlling the preparation of beverages. More particularly, thepresent invention concerns a brewing process and apparatus, including anelectronic controller, conceived to control the process of makingfreshly-brewed hot beverages obtained by filtering with hot, pressurisedwater from ground or minced edible products such as tea, coffee, herbalremedies and the like.

BACKGROUND OF THE INVENTION

This invention is aimed for use in fully automatic hot beveragedispensing machines for homes, offices or so called food-service—orHoReCa—sites. The invention apparatus can also be used to dispense hotbeverages from soluble products, i.e. the so-called instant drinks.

Fully automatic beverage dispensing machines, particularly the onesbrewing hot drinks from ground fresh ingredients, are not yet recognisedfor an outstanding quality of their drinks. A manually prepared espressoby a skilled barman (barista) is still seen as a better beverage thanone prepared by an automatic machine.

Steps to prepare a manual espresso have been described in severalpublications. These steps are: ensuring temperature of all componentsinvolved in the dispensing of the beverage is correct; weighing theamount of ground roasted coffee (e.g. 6.5 grams); coffee grindingadjusted to obtain the suitable particle size, making sure that theclimatic conditions, especially relative humidity, do not change idealgrinding size, so as to have a correct brewing time (e.g. 25″ for 40cc.) is regularly achieved; compacting the coffee inside the brewingchamber, usually attached to a handle, with the aim to achieve the rightbrewing time via the correct drag through the coffee cake.

There are many patents directed to using the above concepts forimproving coffee quality.

EP0554650 to Cavazzuti and Annibali teaches that an ideal size ofroasted coffee grind for espresso coffee is between 25 to 395 micronsand preferably 195 to 240 micron.

In FR2477001 to Grossi, the brewer includes a mechanical system to havethe grinder to modify the average particle size of the coffee. Themagnitude of such modification is based upon the discrepancy between thebrewing time effectively needed to dispense one espresso coffee and astandard brewing time (fixed at thirty seconds), considered to be theideal brewing time.

U.S. Pat. No. 4,767,632 to Meier teaches to measure the displacementpath of the compression piston and the time required to dispense apreset volume of beverage, to compare these data to stored data and touse a possible difference between these parameters as means to adjustthe amount of coffee and the size of milled coffee particles whenbrewing subsequent beverages.

U.S. Pat. No. 5,645,230 to Marogna discloses a coffee grinding anddosing apparatus provided with means to detect ambient humidity and toaccordingly adjust the grinding blade distance to provide a finer orcoarser particle size.

The above solutions, however, are not sufficient because several otherfactors may affect the correct dispensing of a coffee.

In some cases deposits of ground coffee build up on the coffee chuteplaced above the brewing chamber: less coffee reaches the brewingchamber until the deposits collapse to discharge a greater amount ofground coffee in the chamber. Variable quantities of coffee in thebrewing chamber may also be due to lack of precise measuring devices:such is the case when the grinder is operated for a pre-set amount oftime, when volumetric chambers are fed with coffees having differentparticle sizes, e.g. because of wear of the grinder.

EP1306040 to Mestek, EP0486434 to Torma and other documents describe aclosing piston in the brewing chamber using a “compensation spring” i.e.a mechanically resilient means to alter temporarily the internal volumeof the brewing chamber. Such a solution relies on the physicalproperties of the spring and on the amount of coffee and pressure ofwater within the brewing chamber and certainly cannot give an adaptativeanswer to conditions dictated by other considerations such as the typeof coffee to be dispensed or desired extraction yield.

The above discussed documents do not address the problems related to thetype of coffee being dispensed, the volume or size of ground coffeeused, or other considerations suggested by market preferences orcost-saving. It must be considered also that the concept of coffee maybe differently interpreted and a coffee machine has to be an answer tothe different requirements of the end users.

Moreover, in a dispensing machine using pre-filled capsules containingground coffee, the capsules cannot undergo any further grinding of thecoffee therein contained and, therefore, this parameter cannot bechanged.

Therefore, there is the necessity of a brewing process and machine thatcan automatically compensate for the many changes of the product or thedispensing conditions in order to have a constant good coffee quality.

There is also the need of a process and a machine that carries out suchcompensation in real time, i.e. during the same brewing procedure.

SUMMARY OF THE INVENTION

It is an aim of the invention to solve the above problems and to providea brewing process and apparatus that constantly maximize the quality andthe extraction yield of hot beverages obtained from ground freshingredients filtered in a brewing chamber by correction of parameters.

One further aim of this invention is to illustrate a brewing system thatnot only adapts to changed conditions within pre-set thresholds, butthat adjusts its settings by monitoring the brewing conditions astransmitted by the brewing system's sensors during the brewing cycle.

One further aim of the present invention is to reduce the splashing ofcoffee usually associated to a fixed beverage outlet spout's height ofbeverage dispensing machine utilizing beverage containers bearingdifferent rim heights.

Said aims are achieved by means of the present invention, that relatesto a process of controlling the brewing of hot beverages according toclaim 1.

The present invention also relates to a beverage dispensing apparatusaccording to claim 7.

The present invention provides a process and an apparatus to control,monitor and adjust the brewing process according to one or moreparameters that can be stored in the controller's memory of the brewingsystem.

According to the invention, the beverage dispensing apparatus has atleast two pumps; preferably said pumps are in series connected.

According to another preferred aspect of the invention, the beverageflow rate is adjusted by controlling the flow rate of the hot waterentering the brewing chamber. This is done by using more than one pumpor by changing the water pump speed or by using a valve means thatdeviates part of the flow or limits the same.

The use of two or more pumps in series make it possible to dramaticallyreduce the time required for dispensing the beverage.

The invention process can also compare at least one of the datamonitored by the same controller during the brewing step with at leastone previously stored data and, as effect of such comparison, directsand controls through appropriate means the best real-time adaptation ofthe current brewing cycle towards ideal brewing conditions.

In other words, the present invention monitors and changes, if necessaryduring the same brewing process, the brewing process parametersaccording to a number of parameters that are set in the controller'smemory of the brewing system.

According to a preferred aspect of the invention, the real-time datadetected are the incoming hot water or the dispensed beverage flowrates, and the parameter to be adjusted is selected from the hot waterfed to the brewing chamber or the beverage flow rate or theircombination.

According to a further aspect of the invention, the beverage flow rateis adjusted by modifying the brewing chamber volume; to this purpose,the apparatus comprises one or two pistons independently controlled bymotors, for the brewing chamber in order to modify the volume of saidchamber.

More generally, the means of modifying the beverage flow rate areselected from at least one of: means of modifying said brewing chambervolume; means of modifying the flow rate of hot water entering the saidbrewing chamber; possibly also means of controlling the output ofbeverage from the brewing chamber. In addition, means of modifying thegrinding parameter of the coffee can be used, too.

The output control means can be implemented by a valve means on theoutlet duct for the beverage, said valve operation being controlled bythe controller in a real-time feed-back system.

According to a further preferred aspect said aims are achieved bysetting parameters for a programmed sequence of the operations requiredto complete the beverage brewing cycle and, monitoring both stored dataand actual data obtained during the brewing step, by adjusting theflow-rate, possibly also the pressure in the brewing chamber and theaverage size of the particles, in order to approximate the dispensingpath as defined by a range of ideal dispensing curves relating flow-ratewith time, pressure and liquid volume for each stored beverage sequence.

In particular, control of the flow-rate of the beverage and of thesequence of brewing steps is carried out through the use of one or twomotors that are independently operating one or two pistons sealing thebrewing unit, at least one flow-rate detector and valve means placed influid connection upstream to the brewing chamber, hot water feedingmeans and beverage outlet means, liquid waste discharge means and acontroller board connecting the different components.

By controlling and adjusting the flow rate of the hot water fed to thebrewing chamber it is possible to improve the quality of coffee brewedfrom capsule, where compression and particle size are not adjustable.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be further disclosed with reference to theenclosed non-limiting drawings, where

FIG. 1 is a lateral view of an apparatus according to the invention atthe end of a dispensing step;

FIG. 2 is a top view of the apparatus of FIG. 1;

FIG. 3 is a sectional view of the apparatus of FIG. 1;

FIG. 4 is a sectional view of the apparatus with the two pistons alignedbefore reaching the brewing position;

FIG. 5 is a sectional view similar to FIG. 4, with the pistons in thebrewing position;

FIG. 6 is a sectional view similar to FIG. 5, where the brewing chamberis larger and in a different position;

FIG. 7 is a scheme of a water circuit for controlling the water flowrate;

FIG. 8 is a lateral sectional view of another embodiment of the brewinggroup of the invention;

FIG. 9 is a top sectional view of the group of FIG. 8;

FIG. 10 is a front sectional view of the group of FIGS. 8 and 9, and

FIG. 11 is a further scheme of a water circuit according to theinvention.

DESCRIPTION OF PREFERRED EMBODIMENTS

With reference to FIGS. 1-6, the brewing apparatus 1 according to thepresent invention is comprising a preferably cylindrical brewing chamber2, made of metal such as stainless steel or brass, or teflon coatedmaterial or plastics, with at least one side 3 that can be open fordischarging the spent material from which the beverage was brewed.

Two brewing pistons 4, 5 are provided at opposed ends of the chamber 2,when in use, to hermetically seal it during the brewing step. At leastone piston (5 in the shown embodiment) is displaceable from an openposition in which piston 5 is outside the chamber (see FIG. 2) to removethe brewed material, to a closed, brewing position. Means to control themaximum displacement of each of said pistons so that the minimum volumeinside the chamber is not less than a preset value are also provided;generally, such value is 5-6 cc.

Two filters 6, 7, are mounted facing each other on the top area of eachof the pistons 4 and 5. The filters are provided in a known way with aplurality of holes, preferably having regular sizes and diameters withinthe range of 0.15 to 1 mm and positioned to have an optimal waterdistribution and extraction of the coffee cake.

The pistons 4 and 5 are operated by two independent motors 9 and 8,respectively, to which the pistons are connected with means adapted tomove the two pistons axially respective to the brewing chamber. Themotors, preferably with direct current supply, are connected to wormscrews 8A and 9A that are acting on blocks 10 and 11 to move themupwards or downwards. Blocks 10 and 11 are connected to pistons 4 and 5,respectively, so that both pistons can be moved in both forward andbackward directions, independently from the other piston or othercomponents associated to the brewing unit.

The motors 8 and 9 can independently invert the sense of their rotation,and are activated by a micro-processor-equipped electronic controllingboard, which includes a power-board suitable to drive the two motorsindependently and monitor, by means of the impedence or other signal,the load applied against it. This parameter is used to determine thepressure opposed by the ground ingredient compressed in the brewingchamber to said pistons. Both motors can be equipped with means todetect the displacement length of the associated piston. Suitable meansare e.g. an encoder, a Hall sensor, opto-switches and similar.

One of the pistons, piston 4 in the shown embodiment, is provided with aport 12 or similar means of feeding a pressurised, hot water from asource not shown to the brewing chamber 2. Beverage outlet means 13 fordischarging the brewed liquid into the user's beverage container areassociated to the piston 5, i.e. integral with it, and are moved withpiston 5. Outlet means 13 shown in FIGS. 1-6 comprise a rigid duct towhich a further, flexible, duct (not shown) is connected to deliver thebrewed beverage to the cup.

FIGS. 8-10 show another embodiment of the invention apparatus, whereinsimilar elements are referred to with the numerals used in FIGS. 1-6,with the addition of 8.

In this embodiment, the two pistons 84 and 85 are coaxial withrespective worm screws 89A and 88A that are each operated by an electricmotor (not shown) through shafts 28 and 29 positioned at mid height ofthe brewing group. Shafts 28 and 29 are respectively connected tovertical shafts 30 and 31 that are operating gears 32 and 33 that areconnected to worm screws 88A and 89A. Filters 86 and 87 are provided oneach piston to filter the ground coffee as previously explained. In FIG.8 a chute 34 for the ground coffee is also shown.

With reference now to FIG. 7, the apparatus according to the inventioncomprises a pump 14, to create the required pressure for the brewingprocess, in fluid connection with the water inlet 12 of the brewingchamber 2 and connected to a water source such as a water reservoir 15.The preferred flow-rate is at least 0.7 to 10 cl./sec, usually 1-2cl/sec for espresso coffee, and the pressure of the hydraulic circuit iswithin a range from 0.1 MPa and 2.0 MPa, and preferably within the rangeof 0.3 to 1.8 MPa.

Pressurised water leaving pump 14 is heated at temperatures ranging from70 to 110 degrees Celsius, preferably between and 100° Celsius using apressurised water heating device 19 such as a boiler-tank orflash-heater supplied by water reservoir 15 (or water mains).Temperature control means 20 are also provided, associated with thewater conduits, brewing chamber 2 or beverage conduits; means 20 areadapted to transfer real-time information (i.e. actual data detectedduring the brewing of the beverage) concerning the temperature of atleast one of the component amongst the heated components of the circuitother than the water heating device to a controller board 16.

The scheme of FIG. 7 also shows metering means 17 to detect the flow ofthe dispensed beverage or, alternatively, means 18 for detecting theflow rate of the water fed to brewing chamber 2. Both these means, aswell as the other sensors means of the invention apparatus, areconnected to controller board 16 via circuitry or via transponders.

Preferred flow-meters have a scanning unit allowing to controldifferences in the flow at least as low as 0.5 ml/sec, and preferably0.1 ml/sec; additionally a flow-meter detector, a weight sensor, a flowdetector or other methods to verify the out-going flow-rate, can beplaced in the beverage outlet means to monitor effective real-timeoutput of the dispensing apparatus.

According to the invention, controller board 16 has digital memory meansand means apt to transfer and download from external sources settingsconcerning the different phases typical of the brewing process, thiscontroller board being logically or electrically connected to allelectrically operated components comprised in the brewing system andbeing preferably equipped with a micro-controller having at least 28KRam memory and a 5 Ghz clock.

Digital software is integrated in the controller board, or is providedin logic connection to board 16. The software is developed to controland direct the several means, sequencing them in proper order, aimed atcontrolling the different steps of the brewing cycle. The parameters ofthe preferred brewing sequence are stored for each individual drinkavailable to the user in the controller's memory.

The parameters of the brewing sequence can be adjusted in a remotelocation, using a PC with dedicated software. New settings can then beloaded onto the controller's memory using a flash-Eprom, an electronictag, a transponder or other system of remote transfer of electronicfiles. Some, preferably simpler, parameter settings may be renderedavailable for modification to the users of the dispensing appliance byusing the means for forwarding an input command to the controller suchas push buttons or keyboard or touch-screen, or through other devicessuch as a hand-held, wire or wire-less terminal to be used at themachine's site. Current active settings are stored in the controller'smemory and can be retrieved for remote control. The controller may useany of the systems available to the skilled in the art to retrieve andre-load these data, such as GPRS, a modem connection for Internet accessto a central data-bank, contact-less memories, a hand-held terminal,flash-eproms or other suitable means of transfer of the digitalinformation. The operational software, typically included in thecontroller's board, allows also to pre-select different degrees ofsensitivity for the adjustment process.

At least one storage container 21 for coffee beans and a grinder 22attached to it or, alternatively, a container for fresh ground edibleproduct such as coffee or tea, or with means adapted to provide ametered amount of coffee grounds to the brewing chamber are provided ina way known per se in the art. In addition, one or more containers forinstant soluble ingredients can be provided.

The metering means to control the amount of coffee dispensed in thebrewing chamber can be volumetric or time-based, using an inferencetable, for instance listing time of operation of the grinders andexpected volumes of coffee depending on average particle size of thecoffee.

In preferred embodiment of the invention the storage container 21 isprovided with sensor means 23 to detect the air relative humidity andtemperature in proximity of the coffee container or within it. Sensor 23and grinder 22 are connected with board 16 to provide and receiveinformation.

The apparatus according to the invention also comprises metering means(not shown) to monitor the exact length of displacement of each piston,for instance detecting it by inference, using encoder-equipped orstep-by-step motors or electro-mechanical systems, or couplingelectronic sensors, using systems available to the skilled in the artsuch as Hall-effect sensors or others, to the respective motor shafts ofthe two motors controlling the brewing pistons or to parts of saidpistons, in the latter case to detect even without inference the actualpositions of the two, distinct pistons.

The apparatus is further provided with means for forwarding an inputcommand recognised as valid input command by the controller, this inputcommand being used to deliver instructions to the controller concerningthe type of beverage requested by the machine's user, for example acustomer or the bar-tender. The input method may include a keyboard, forinstance of a numerical or alphanumerical type, a simple membrane panelusing pictograms or interactive panel, such as a touch-screen LCD, orany other common physical interfaces for sending a brewing or dispensinginstruction to a machine. The chosen option can be sent also via a tagor transponder directly to a tag scanner or tag reader in the proximityof the apparatus and digitally connected to the controller board.Alternatively the input commencing the brewing cycle can be provided tothe controller by any signal, for instance generated by the insertion ofa coin or other validation of credit, recognised as acceptable inputsignal by the machine controller.

The above means comprise known means to forward to the user of theapparatus information concerning the status of the machine, such as LEDindicators, an LCD or plasma screen, a vacuum-fluorescent display, aswell as means to forward digitally the information to a remote location,physically separated from said apparatus.

According to the invention, the preferred parameter to be controlled andpossibly adjusted is the flow rate of the hot water fed to the brewingchamber 2 or of the hot beverage leaving the brewing chamber.

As mentioned, the alterations or adjustments of the brewing parametersinvolve the adjustments of flow rate of the hot water fed to the chamberand/or of the volume of the chamber. additionally, size (e.g. averageparticle size) of the ground material for brewing, pressure of the hotwater, absorption rate of the motors controlling the pistons or thepressure of the outgoing beverage liquid or the diameter of the orificescreating the total free passage in the filter placed on (before) theoutlet can be adjusted, too.

It is preferred to control, i.e. to change or adjust, the flow rate ofthe hot water, or the chamber volume rather than reducing the beverageflow rate with a valve on the beverage outlet. It is in fact easier andcleaner to change these parameters than altering directly the hotbeverage flow rate: a valve means positioned downstream the brewingchamber (or solubilizing chamber) is inevitably contacted with thebeverage, with possible problems of cross-contamination when dispensingdifferent beverages types, building up of deposits, bacteriacontamination and similar problems.

It was found that when the flow rate of the incoming hot water isadjusted to maintain constant the amount of coffee brewed per unit time,i.e. to maintain a dispensing time within the range of 10 to 30 secondsand preferably from 15 to 25 seconds, most of the other parametervariations can be automatically taken into considerations and corrected.

In other words, according to the invention,

the hot beverage or hot water flow rate is detected: this is thereal-time data of a brewing process to be monitored;

the detected real-time flow rate data is compared with the stored dataconcerning hot beverage flow rate, the stored flow rate can be differentfor different ground edible ingredients or drink types;

if a correction has to be carried out, the flow rate of the hot beverageis corrected by altering the volume of the brewing chamber or byaltering the flow rate of the hot water fed to the brewing chamber.

In a preferred embodiment of the invention there are no mechanical meansto control the flow of hot beverage between the brewing chamber and thebeverage delivering means, i.e. the outlet from which the beverage isdelivered into a cup: any alteration of the brewing parameters iscarried out in the brewing chamber or upstream the same.

In an embodiment of the invention, in order to adjust or alter the hotwater inlet flow rate, the following procedure is followed.

As soon as a pressure is established in the brewing chamber and thecoffee cake is progressively penetrated by water, the flow-rateindicated by the metering device, at least one of which is in fluidconnection with the brewing chamber's water inlet means, is used as afeedback signal to alter brewing parameters, after a programmable delayor starting from the pump switch on.

In case of no flow-rate indication even after the programmable delay,the dispensing apparatus is set into an “out of order” condition andappropriate interface displays such information for the machine users.

Assuming a positive flow-rate reading, as monitored by at least aflow-rate indicator placed before the brewing-chamber and in fluidconnection to the same, the controller compares the reading to thecomparable value of the ideal dispensing curve associated with thespecific beverage being dispensed.

If there is a discrepancy between the two data, in a first embodiment,at least one of the piston's displacement length is changed as aconsequence of the feedback, so that the volume of brewing chamber 2 isadjusted and the flow rate is maintained as close as possible to thepre-set dispensing curve. The minimum displacement step controllable bythe controller should not vary the internal volume of the chamber forvolumes higher than 0.5 cc. preferably 0.3 cc.

In a second embodiment of the invention, the flow rate of water fed intothe brewing chamber is changed and adjusted. This can be carried oute.g. by using a pump having variable speed, such as a rotative pump, todispense pressurised water into the brewing chamber. A change of speedcan be obtained also by changing the frequence of vibration of avibration pump.

Alternatively, as shown in FIG. 7, when the sensor 18 providescontroller 16 with the information that the flow rate of the incomingwater should be reduced, valve 24 is operated to send a portion of theflow of water to a circuit including plenum chamber 25 and connected toreservoir 15, or to the pump or to a discharge means.

A preferred embodiment is shown in FIG. 11, where the apparatus of theinvention comprises two pumps 14 and 14A connected in series. The twopumps are preferably vibration pumps and are operated separately or atthe same time according to the actual requirements of the brewingprocedure. Suitable pumps are e.g. those manufactured by Ulka (Italy).

It was found that when two or more pumps are connected in series, it ispossible to operate both pumps at the same time and obtain an increaseof the flow rate of up to about 80% and a reduction of the dispensingtime of about 45-50%. These values are obtained when two identicalvibration pumps are connected in series but not if they are connected inparallel. By using two Ulka E7 vibration pumps, the flow rate increasedfrom 2.45 ml/sec to 4.23 ml/sec and the dispensing time of an espresso(having a volume of about 47 ml) decreased from 20.4 sec to 11.2 sec.Instead of two (or more) identical pumps, two or more different pumpscan be used.

The process will involve starting first one pump or both pumps,according to the requirements of the beverage to be dispensed: e.g. afilter coffee involving e.g. 150 ml will initially require the use ofthe two pumps to maintain the dispensing, i.e. brewing, time within therequired range of 10 to 35 seconds. If the data detected during thebrewing step are different from the stored data, one pump will bestopped or slowed to reach the required values.

As mentioned and below exemplified, further data may additionally bedetected and further parameters may be adjusted or changed besides theflow rate. The following sequence of operative steps for the chosenbeverage—for instance an “espresso” coffee—is depicting an embodimentmaking a full use of all the parameters and real-time data.

The operating of the dispensing apparatus starts when the machine's userforwards an input command to the controller. Firstly the correct tuningof the grinding level is to be checked. Sensors 23 located near thegrinder 22 or coffee container 21 detect the current value of relativehumidity, and optionally also of temperature, in the air. The controller16 includes software that allow to store data concerning historiccomparable data, as monitored by said sensors at intervals of time thatare programmable by the manufacturer of the apparatus.

The controller's software can use several methods to evaluate theavailable data, both current and historic, for instance adding eachseries of said stored data or parts of them, thus calculatingstatistically meaningful data, such as arithmetic or compounded means. Apreferred compounding criteria is the time-lag between monitoring timeand time of brewing, so that the readings of the last twenty-four hours,preferably of the last one to nine hours should bear more weight.

The controller's software preferably includes means to establish atrend, for example comparing current readings to the stored datareadings in different intervals of time, such as for instance during thelast one to twenty-four hours, conveniently stored in the memory.

Contrary to available systems, in the present invention comparison ofpreviously recorded data to current readings is used to establish apreferred criteria to influence the adjustment of the grinder's blades,so that the user of the apparatus can opt to maintain frequentvariations based on real-time data or, more traditionally, a slower paceof trimming the blades' distance, for instance for less stringentquality standards.

The motor setting the distance of the grinder blades, provided withmeans to detect the actual distance of the blades or alternatively tomeasure the length of the displacement of the motor controlling theblades, for instance from a full closed position to the actual position.When a difference from stored data higher than a pre-determinedthreshold is detected, the motor is actuated to adjust the bladesdistance accordingly. The pre-selected dose of coffee (e.g. set at 6.5grams in the controller), having a pre-determined average particle sizeaccordingly to the monitored relative air humidity and trend values aswell as to the type of selected beverage, is dispensed in the brewingchamber 2 or 82.

After grinding the coffee beans, the brewing step is carried out.

In general, four distinct steps are provided for in the brewing cycleaccording to the invention and the brewing system includes sensors aptto provide to the controller board information concerning the hotbeverage flow rate, the hot water flow rate, the length of thedisplacement of the one or two pistons and the power absorption of themotors connected to them, the temperature of means apt to transfer heatto the brewing chamber. As previously mentioned, all the sensors areconnected either via hard-wiring or with transponder-type connection tothe controller board 16, which is also receiving information concerningthe setting of the coffee grinder's blades feeding the brewing chamberand beverage type required by the user, thereby selecting a group ofpre-set parameters during that specific brewing cycle.

The brewing cycle starts when, the brewing chamber having been filledwith the metered amount of coffee, closing piston 5 is moved from anopen, filling position to a closed, brewing position (FIG. 5).

In this initial phase, at least one of the motors 8, 9 connected to thepistons reaches a pre-set, programmable absorption level set as athreshold parameter in the controller's memory, for immediatedisconnection of the motor drive once the pre-set level is reached.

The set absorption level does not depend only on the amount of coffee,but for instance from programming data instructing closing the brewingpiston or pistons with a pre-determined amount of coffee inside thechamber. Said pre-determined amount of coffee can be stored as historicdata coupled with the absorption reading to establish a correlation tobe used for statistical information and preventive maintenanceinformation.

The coffee cake is now compressed from the irregular shape determined bythe means used to convey it to the brewing chamber, for instance apyramidal shape, into a cylindrical shape, with a compression level thatis depending on said pre-set threshold parameter.

When the piston has reached the programmed displacement length with thecompressed coffee cake, a programmable amount of water can be sprayedover the coffee cake. It is preferable to use a pump 14 with meansadapted to control the flow of the pump, so that this spraying step canbe performed with a reduced flow-rate, possibly at least 40% lower thanthe one usually used in the brewing step.

This optional step, is performed in order to pre-wet, when needed andwith a programmable quantity of pressurised hot water from the waterinlet means, the coffee cake, to minimise the negative effects in termsof beverage quality and extraction yield that preferential routes in thecoffee cake tend to create.

After the pre-set amount of water has been dispensed over the coffeecake, the brewing unit pauses for a pre-set amount of time, less thantwenty seconds, preferably between one and ten seconds.

Alternatively, the beverage outlet can be temporarily closed to create apressure increase to obtain a similar pre-wetting step, without a pause.

The whole pre-wetting step can be omitted, especially if long coffeesare to be dispensed, so to emphasize the different nature—forinstance—of a so called “regular coffee” drink of 300 ml from atraditional espresso coffee, where pre-wetting is most used and higherextraction yields are usually preferred.

When beverages based on minced leaf tea, mate or herbal remedies are tobe dispensed, longer throws of pre-wetting water and longer pausesbefore the commencement of the real brewing phase, are implemented tomaximize quality of extraction.

Similarly, if soluble drinks are to be used in the chamber, pre-wettingwater can be used to maximize the dissolution in the liquid of thesoluble ingredient.

The second step starts when the controller activates the meansassociated at least to one of the two brewing pistons so that thebrewing chamber is brought to a closed, air-tight, brewing position.

Motors 8 and 9, in one embodiment, are subsequently deactivated so thatthe two pistons are held in a pre-programmed position, depending on thetype of beverage to be dispensed, expressed in terms of length ofdisplacement or, preferably, power absorption of each of the two motorscommanding the pistons.

In one embodiment, motors are adapted with means that allow said motorsto remain activated during the compression of the coffee cake, untilthey reach a threshold level in terms of absorption, and subsequentlyduring the proper brewing phase, so that the absorption of at least oneof the motors can be used as feedback criteria.

Data concerning displacement length and power absorption, or dataexpressing the relation between the two, as well as their frequency, arestored in controller 16 memory for possible preventive maintenanceinformation to be down-loaded from the controller's memory.

Brewing with pressurised means is usually performed in two distinctways: either from top to bottom of the cake, or from bottom towards thetop. In the embodiment shown in the figures, the brewing is performed inthe latter way, although the other method is equally usable.

Both embodiments solve one problem associated with users utilising abeverage dispensing machine with beverage containers of different shapesand—particularly—heights, such as porcelaine mugs, espresso cups, coffeecups, small jugs and similar.

Typically these containers can be adapted to fit into the dispensingarea of the dispensing apparatus, but their rim heights commonly varybetween 4 and 30 cm, most frequently between 6 and 20 cm.

To solve this problem a coffee outlet spout connected to the associatedpiston and its beverage outlet means is used, whereby the programmeddisplacement lengths of both pistons during the dispensing phase allowthe outlet spout 13, accordingly to the pre-set beverage preparationrequired, to move to one of a number of pre-set positions.

The outlet spout can thus be displaced right above the rims of cupshaving different rim heights from the bottom, such as a cappuccino cupor an espresso cup or a mug, or alternatively the outlet spout canaccess different outlet means adapted for instance to dispense one ortwo coffees at a time.

The controller, depending on pre-set parameters, can execute brewingcycles having for each piston different displacements lengths in orderto maintain, for the chosen type of beverage, the correct pressure ofthe coffee cake whilst minimising the distance between container's rimand the flow of prepared beverage pouring from the outlet spout, or alsoto allow the outlet spout to access an alternative beverage outlet path,for instance to divert the outlet to two different dispensing outlets.

Because the pistons can both be moved, raising or lowering the outletspout's height, with reference to the beverage container's rim, thelatter can thus be controlled independently on the amount of coffee usedor to the type of coffee desired, to match the container used in thereceptacle area. The height of the beverage outlet spout depends on thepre-set type of beverage or beverage container required by the user,that is following pre-set parameters in the controller's memory.

In the drawings embodiment, the brewing unit can move the beverageoutlet means height in a defined range, in this case between 10 cm forsingle brewing cycles and 7 cm for double brewing cycles.

As soon as the pistons have completed their programmed displacementpaths, hot water is fed into the brewing chamber via the filterpositioned on the piston equipped with water inlet means, i.e. filter 7or 87 of piston 4 or 84. The hot water inlet means are in fluidconnection with the pump(s) 14 and 14A, possibly to one three-way valveor preferably to two separate valves to separately manage incoming hotwater and residual liquid coffee waste and to the flow-rate meteringdevice 18.

The flow rate control of this step is carried out as previouslydiscussed, i.e. by using one or more of a plurality of vibration pumps,altering the pump speed, or altering the chamber volume. Additionally,reducing the flow rate through a valve can be carried out.

Ultimately, when the pre-set volume of water has been completelydispensed into the brewing chamber and from this to the final container,the controller initiates the sequence aimed at discharging the usedcoffee grounds.

Firstly, at least one of the pistons is moved, by the appropriatetransmission means, from the presently final, closed, brewing positionto a position defined by a displacement length longer than the one ofthe said final, closed, brewing position. Several displacement lengthare stored in the controller's memory and can be used followingpre-defined matching criteria to different types of coffee beveragebeing dispensed or amount of liquids allowed in the waste used coffeegrounds.

This compressing movement is made in order to increase the pressureexisting in the brewing chamber, so that a lesser residual amount ofliquid is maintained inside the coffee cake due to the higher pressurethus achieved. As soon as the displacement length value is reached, thecontroller opens a water conduit (not shown) to discharge the residualamount of coffee and water present in the supplying pipe, the coffeecake and brewing chamber.

This can be alternatively done with two separate valves, each of themcontrolling separately the water inlet to the brewing chamber and thepurge conduit aimed at discharging the liquid remaining at the end ofthe brewing cycle inside the brewing chamber, coffee cake and waterconduits, or alternatively with one three-way valve, whereby preferablythe former embodiment, bearing two separate valves, allows to includeseparate controls to the inlet and to the outlet means so that thebrewing cycle can displace in time the closing of the water inlet andthe opening of the discharge means for the used, waste liquid residues.

It is useful to notice that all mentioned parameters are recorded in thecontroller's memory for statistical purposes and can be at any timeretrieved and adjusted by means available to the skilled in the art, asmentioned.

More in detail, the invention apparatus comprises a software programimplementing a process according to any claims 1 to 6. Preferably, thesoftware program records all data concerning the process and morepreferably the software program that allows retrieval of all dataconcerning the process.

1. A process of controlling brewing and dispensing of beverages from abrewing chamber (2; 82) provided with means (6,7; 86,87) for filteringhot pressurized water through ground edible ingredients, comprising abrewing procedure that includes steps of feeding the hot pressurizedwater through the ground edible ingredients and into a brewing chambervolume of the brewing chamber; adjusting a flow rate of the hotpressurized water fed to the brewing chamber (2; 82) with a plurality ofpumps (14, 14A); brewing contents of the brewing chamber to formbeverages; and dispensing the beverages.
 2. The process according toclaim 1, wherein said pumps are connected in series.
 3. The processaccording to claim 1, wherein the pumps are operated separately or atthe same time as applicable in accordance with the brewing procedure. 4.The process according to claim 1, further comprising storing data inmemory of a controlling unit (16), further comprising carrying out thefollowing steps with the controlling unit (16): a) detecting real-timedata that includes at least beverage flow rate data of the beveragesbeing dispensed during said brewing procedure; b) comparing saiddetected real-time data with data stored in said memory to determinewhether a correction to actual beverage flow rate should be made; and c)adjusting a beverage brewing parameter to bring the beverage flow ratein line with said stored data by selecting the beverage brewingparameter from the group consisting of the flow rate of the hotpressurized water fed to said brewing chamber (2; 82) and the brewingchamber volume.
 5. The process according to claim 4, wherein saidadjusting of the brewing parameters is carried out in real-time, duringthe brewing procedure.
 6. The process according to claim 1, furthercomprising the steps of detecting humidity data and adjusting particlesize of said ground edible ingredients according to said humidity data.7. An apparatus (1) for controlling brewing and dispensing of beveragesfrom a brewing chamber (2; 82) provided with means (4-7) for filteringhot pressurized water through ground edible ingredients, comprisingmeans for feeding the hot pressurized water through the ground edibleingredients and into the brewing chamber; means for adjusting a flowrate of the hot pressurized water fed to the brewing chamber (2, 82)with two or more pumps; means for brewing contents of the brewingchamber within a brewing chamber volume to form beverages; and means fordispensing the beverages.
 8. The dispensing apparatus according to claim7, wherein said pumps are connected in series.
 9. The dispensingapparatus according to claim 7, wherein said pumps are vibration pumps.10. The dispensing apparatus according to claim 7, wherein said pumpsare differ from each other.
 11. The apparatus according to claim 7,further comprising means (17,18,20) for detecting brewing parameters asreal-time data when brewing said beverage, a controlling unit (16)having memory and means for storing data in the memory and for comparingsaid real-time data to a set of stored data to determine whether acorrection to the brewing parameters should be made, means for detectingsaid beverage flow rate and means for adjusting a beverage brewingparameter to bring the beverage flow rate in line with said stored datawith equipment selected from the group consisting of means for modifyingthe flow rate of the hot pressurized water fed to the brewing chamber(2; 82) and means for modifying the brewing chamber volume.
 12. Theapparatus according to claim 7, further comprising at least two pistons(4,5) for said brewing chamber (2;82) independently operated by motors(8,9).
 13. The apparatus according to claim 12, further comprisingsensors having an absorption rate of at least one of the motors (8,9)operating said brewing pistons (4,5).
 14. The apparatus according toclaim 11, wherein said means for modifying the flow rate of hotpressurized water entering the said brewing chamber comprises afeed-back circuit branched from a water circuit to feed the hotpressurized water to said brewing chamber, said feed back circuitincluding a valve (24), a plenum chamber (25) and a duct (27) connectingsaid plenum with said water circuit.
 15. The apparatus according toclaim 7, wherein said means for altering brewing parameters furthercomprises means (22) for modifying grinding parameters of the beverages.16. The apparatus according to claim 7, wherein the ground edibleingredients are selected from the group consisting of coffee, tea andherbal remedies.
 17. The process according to claim 1, furthercomprising selecting the ground edible ingredients from the groupconsisting of coffee, tea and herbal remedies.